Abstract: A surface light source device, comprising a light source (2); a light conductor (1) which has a light incident face (11) on at least one side end surface thereof which confronts the light source (2), and a light emitting face (12) on one surface thereof which is substantially perpendicular to the light incident face (11); and a light angle varying sheet (3) which is disposed at a side of the light emitting face (12) of the light conductor (1), wherein at least one of the light emitting face (12) and a back surface (13) of the light conductor (1) comprises a minute structure having an average slant angle of 0.5 to 7.5 degrees. The light angle varying sheet (3) may comprise a prism sheet having a plurality of prisms (31) which are formed parallel to one another on at least one surface thereof.

Abstract: A surface light source device, comprising a light source (2); a light conductor (1) which has a light incident face (11) on at least one side end surface thereof which confronts the light source (2), and a light emitting face (12) on one surface thereof which is substantially perpendicular to the light incident face (11); and a light angle varying sheet (3) which is disposed at a side of the light emitting face (12) of the light conductor (1), wherein at least one of the light emitting face (12) and a back surface (13) of the light conductor (1) comprises a minute structure having an average slant angle of 0.5 to 7.5 degrees. The light angle varying sheet (3) may comprise a prism sheet having a plurality of prisms (31) which are formed parallel to one another on at least one surface thereof.

Abstract: An electrophotographic photosensitive member is constituted by disposing a photosensitive layer including a charge generation layer and a charge transport layer on an electroconductive support. The charge transport layer has a thickness of at most 12 .mu.m and is formed by dispersing therein particles having a particle size of 1-3 .mu.m at a density of 1.times.10.sup.4 -2.times.10.sup.5 particles/mm.sup.2. The charge transport layer and the particles described above provides a difference in refractive index of at least 0.10.The photosensitive member is effective in providing good images free from black spots and interference fringes and with a good gradation-reproducing characteristic when used as a structural member of a process cartridge and an image forming apparatus.

Abstract: A transfer material carrying member is described which has at least two resin-containing layers. The relative dielectric constant (E1) of the surface layer and the relative dielectric constant (E2) of the layer(s) other than the surface layer show a ratio (E1/E2) satisfying the following expression of 0.02.ltoreq.(E1/E2).ltoreq.0.7. The carrying member shows a high transfer efficiency and is able to provide high quality images for a prolonged period of time.

Abstract: A carrier for use in electrophotography has carrier particles. The carrier particles each comprise a carrier core particle and a resin for coating the carrier core particle and having a resistivity of 10.sup.10 .OMEGA..multidot.cm or above under conditions of a temperature of 23.degree. C. and a humidity of 50% RH. The carrier particles have an average particle diameter of not larger than 100 .mu.m and a resistivity of 10.sup.10 .OMEGA..multidot.cm or above. The carrier particles comprise not less than 80% by number of resin-coated carrier particles whose carrier core particles are each coated with a resin in a coverage of not less than 90%.